Automatic switch-off assembly for feed spools in textile machines

ABSTRACT

An automatic switch-off assembly in the operation of individual feed spools on textile machines essentially including a balloon thread guide connected to a holder on the machine frame in such a manner that the thread guide as a monitor or sensing element is urged to tilt against the normal tension exerted by the thread running thereagainst and as a guide element is also rotatable on said holder laterally away from the normal balloon thread path, both the tilting and rotating movements actuating a switch to its shut off position for at least the associated operating unit of the textile machine.

United States Patent" Rehn et al.

1151 3,701,247 1451 Oct.31,1972

[s41 AUTOMATIC SWITCH-OFF ASSEMBLY FOR FEED SPOOLS IN TEXTILE MACHINES[72] Inventors: Karl-Heinz Rehn; Klaus Detlef Otten, both of Remscheid,Germany [73] Assignee: Barmag Barmer' MaschinenfabrikAktiengesellschaft, Wuppertal, .Ger-

many

[22] Filed: 'May 13,1971 21 App1.No.: 142,903'

[30] Foreign Application Priority Data 2/1956 Saunders et al.", ..242/37X 10/1960 Bahnson,.lr. ..s7/'s1x 2,977,663 4/1961 Evans ..57/81 X2,984,964 5/1961 Bates; ..57/8lX 3,132,466 5/1964 Preisser ..57/8l3,272,048 9/1966 Archer ..57/8l 3,438,188 4/1969 Boggs ..242/37 XPrimary Examiner-John Petrakes Attorney-Johnston, Root, OKeeffe,'Keil,Thompson & Shurtleff v 7 157 A A ABSTRACT.

An automatic switch-off assembly in the operation of individual feedspools on textile machines essentially including a balloon thread guideconnected to a holder on the machine frame in such a manner that thethread guide as a monitor or sensing element is urged to tilt againstthe normal tension exerted by the thread running thereagainst and as aguide element is also rotatable on said holder laterally away from thenormal balloon thread path, both the tilting and rotat ing movementsactuating a switch to its shut off position for at least the associatedoperating unit of the textile machine.

14 Claims, 7 Drawing Figures PATENTEDnc-m 1972' 3.7401. 247

sum 1 or 2 )NVENTORS. KARL-HEINZ REHN KLAUS DETLEF OTTEN This inventiongenerally relates to a switch-off device for use in combinationwithtextile machines in the event of thread or yarn breakage or exhaustionof the supply spool, using ,an electrically operating switching device;

In the textile industry, there are several differentmonitoring systemsfor textile machines which bring either the entire machine or, moreusually a particular machine station or unit, to a standstill in theevent that thread breakage occurs. In particular, thread-monitoringsystems for textile machines are known which include a housing havingarranged therein an electrical switch which is connected toa rocker armor thread sensing lever that contacts the thread to be monitored in sucha way that, if the thread breaks, the rocker arm or lever pivots intoanother position, for example under its own weight or under springpressure, and thereby actuates a switch to bring the machine station orunit affected to a standstill.

In one known thread monitoring system, for example, the travellingthread pulls a probe or sensing lever into its balanced working positionagainst the pressure of a spring. If the thread breaks, the spring pullsthe lever into the switch-off position. The electrical contact is closedby this movement of the lever and the machine or the particular unitaffected is switched off.

In another known device for switching off textile machines in the eventof thread breakage, the sensing lever is arranged in such a way that itcan rotate freely about a pivot, being held in a vertical orsubstantially vertical position by the travelling thread. When thethread breaks, the lever swings around laterally and actuates anelectrical contact in its swivelled or swungout position.

Although these and other knownthread-monitoring systems which actuate anelectrical switch in the event of thread breakage usually functionreliably, they have the disadvantage of occupying aconsiderable amountof space and are often extremely cumbersome. This is particularly sowhere they must be incorporated into modern textile machines, forexample with horizontally or substantially horizontally arranged verytightly packed spindles with only a very narrow gap between theindividual stations or units. Under these circumstances, the spindlechanging operation becomes very difficult to carry out, i.e. fresh feedspools cannot be quickly and easily mounted on the spindles afterstripping off an empty spool.

One object of the present invention is to provide a thread monitoringassembly or device for textile machines which functions both as a threadmonitoring means and also as a balloon thread guide in all of thevarious types of twisting machines, and which does not interfere withthe changing of spools or bobbins. Other objects and advantages areexplained more fully hereinafter. I I

It has now been found, in accordance with the present invention that onecan achieve a very desirable improvement in textile machines of the typegenerally known and described herein by providing in combinationtherewith an automatic electrical switch-off asreceive said thread inrunning contact at the required height of the thread balloon duringnormal operation, a holder to which said thread'monitor is pivotallyconnected so as to be urged in tilting relationship against the tensionexerted by the running thread, said holder also including means torotate said thread monitor about the holder axis laterally away from theaxis of the thread balloon path, and electrical switching means arrangedin said holder for actuation to its shut off position in response tomovement of said thread monitor to its tilted position free of threadtension and alsoin response to movement of said thread monitor to itsrotated position away from said balloon path.

According to the invention, there is thus essentially provided a devicefor switching off a textile machine or one operating unit thereof in theevent of thread breakage at any time or in the event of exhaustion ofthread from a supply spool, no supervision being required. The assemblyin combination with the textile machine includes a thread monitor whichis connected to a holder which in turn is adapted to be fixedly attachedto a machine frame and preferably adjustable in its distance from themachine sothat it can be adapted to the required height of the threadballoon, the monitor thereby being adapted to act simultaneously as aballoon thread guide. This monitor or thread guide is then urged to tiltagainst the effect of the thread tension, the monitor further beingadapted to rotate laterally thereof and to cooperate with a built-inelectrical switch which is brought into its closed or shut-off positionboth in the fully tilted and also in the fully rotated position of thethread guide or monitor.

The thread-monitoring device in the combination according to theinvention enables the thread guide for the balloon to be brought duringoperation into the most favorable position for friction free completionof a winding operation and, when spools are being changed, it can berotated or swung out to provide completely free access to the spindlesand thus does not interfere with the spool changing operation. Theautomatic stoppage of the machine or the particular unit when in theswitch-off position, i.e. after the thread guide has been rotatedor'swung down or away, is'a safety measure against any accidentalswitching on of the machine unit before the spool changing operation hasbeen completed. Optionally the thread guide can be locked both in itsworking position in contact with the running thread, and also in itsswung-out or laterally rotated position by any suitable locking means.This ensures that the thread guide cannot be in-v advertently rotatedand/or tilted to the wrong position.

The invention is described in greater detail below with reference to theaccompanying drawings, wherein:

FIG. 1 is a partly schematic illustration of a first embodiment of theinvention, for positioning the assembly as shown in side elevation belowa horizontally arranged twisting spindle, the assembly being in itsworking position;

FIG. 1A is a cross-sectional view taken on line A-A of FlG.il to showthe arrangement of certain elements in the holder of the assembly;

taneously as a balloon thread guide positioned to FIG. 2 is the sameembodiment as FIG. 1 but shown in its tilted position following threadbreakage;

FIG. 3 illustrates another embodiment of the threadmonitoringarrangement for positioning above a horizontally arranged twistingspindle;

FIG. 3A is a partly schematic and enlarged perspective view of certainelements extracted from the interior of the holder shown in FIG. 3; I 2

FIG. 4 illustrates a slightly modified embodiment including a suitablelocking means for the thread-monitoring arrangement, with the holderpositioned below a twisting spindle; and

FIG. illustrates an embodiment similar to FIG. 4 but positioned above atwisting spindle.

FIG. 1 generally shows'a yarn or thread-monitoring device located belowa typical thread balloon B which forms around aloaded twisting spindle(indicated in phantomlines) asthethread is rapidly withdrawn and twistedor otherwise processed. The balloon thread guide 1 also acts as a threadsensing lever and has a looped wire thread guiding eyelet 2 at its upperand a switch actuating element 4 is arranged at the'lowe'r end ofthelever 1 inside a housing or casing 18. The thread guide 1 togetherwith the switch actuating'element4 are capable of being tilted orpivoted about the axis or pivot pin 3 under the effect of gravity when athread 25 breaks after being in contact with and travelling through theguide 2 as shown in FIG. 1. The switch element 4 isprovided on one sidewith a protruding cam 5 against which there bears or engages a switchingtongue 6 of a microswitch 7. In addition, a guide pin 8 is arranged onthe switching element 4 perpendicularly of the pivot 3. Some of theseelements are more clearly shown in FIG. 1A. j

A forwardly curved cam member 10 is fixed to the flange 11 of a hollowpin 12 which in turn is connected to a stationary holder member 16 ofthe device by another pin 13 and is thereby prevented from rotating. Theholder 16 is preferably adjustably arranged for axial movement in themachine frame F, as indicated for example by the set screw and flangeindicated by S in FIG. 2. The flange of the hollow pin 12 acts inconjunction with a spring 17 fixed at one end to the flange 11 and atits other end to the rear wall or reentrant annular portion of thehousing 18, as a retaining means for-the rotatable housing 18 which isclosed by its cover 19. If the housing 18 is rotated clockwise with itscover 19, a'slide or cammed surface 9 of the forwardly curved section 10causesthe lever 1 to swing abouttheaxis 3 through the cammed contactwith the guide pin 8. As a result, the spring 17 makes a frictionalcontact between the rear wall of the housing 18 and the facing frontwall of the forwardly projecting portion 14 of the holder 16, thuspreventing unintentional rotation. If necessary, this effect can befurther enhanced by a locking mechanism acting in both positions.

If the thread 25 breaks or if it runs off the supply spool, the tongue 6of the microswitch is actuated by the thread guide 1 which is tilted ordropped down, i.e. the microswitch 7 is essentially actuated by theprotruding cam orv finger 5' arranged on the switch actuating element 4,thus closing or opening the circuit, as the case may be, by which theparticular working station or operating unit of the machine iseffectively switched off. v i

The same effect occurs when the housing 18 together with its cover 19 isrotated counterclockwise and locked in this position.

The position which is assumed in the event of threadbreakage is shown inFIG. 2. The lever arm 1 of the thread guide has rotated about the pivotpin 3, thereby swing down or tilt under 'the'effect of gravity in theevent of thread breakage, it is advantageously assisted by a spring 23which loads the switch actuating element 4 against the normal threadtension of the running thread. The switch actuating element 4 can onlypivot or tilt together with the thread guide 21 when the pressure of thespring approaches zero, i.e. when the thread 25 breaks. The thread guide21 with its wire eyelet 22 is turned with switching element 4throughan'angle' of l in comparison with the embodiment .shown in FIGS. 1 and2. I

Once again, as more clearly shown by reference to both FIGS. 3 and 3A,the switch actuating element 4 has a guide pin 8 but in this case, onaccount of the oppositely directed rotating movement in comparison tothe embodiment shown in FIG. 1, this pin 8 cooperates with a curvedsection which has an effective slide way 26 on the opposite side of thepin 8 in comparison to that of FIG. 1. In other respects, however, themode of operation isexactly the same as that described earlier for theembodiment shown in FIG. 1. In this case, the miscroswitch 7 is thusarrangedin exactly the same way as in the firstdescribed embodiment andis connected in such a way that the circuit is closed when the tongue 6swings down,-

In order to-lock the thread guide .1 or 21 in its pivoted or tiltedposition, the embodiments shown in FIGS. 1 to 3 have a cammedpin or lug20 which, when rotated through about its axis, locks the thread guide inits tilted out position. By contrast, FIGS.- 4 and 5 Show a differentform of a locking mechanism. In this instance, a slide member 28 movablein slot 27 in the housing 18 or in the cover l9.can be displaced betweenthe inside of the housing cover and the switching element 4 in such away that the yarn guide or 21 cannot be tilted down into the working oroperating position. Instead of using spring 23 as shown in FIGS. 3 and5, one can also insert simple magnetic means, e.g. a pair of opposedmagnets, as indicated by the double-arrow 29 in FIG. 4. i

So far, theprovision of the thread monitoring arrangement according tothe invention has been described only with reference to horizontally orsubstantially horizontally arranged spindles. However, itv

can also be used advantageously whatever the arrangement of thespindles. Whether one uses the e mbodiment shown in FIG. 1 or theembodiment shown in FIG. 3 is something determined by the strength ofthe monitored thread or yarn. Thus, it is usually necessary to employthe second embodiment in the case of small denier or weak textile yarnsand vertical spindles, the

first embodiment being better suited to. the same arrangement ofspindles and larger denier yarns. In either case, the invention affordsvery desirable advantages in the combination of the balloon thread guideand the thread monitor or sensing lever and also in the possibility ofrotating or swivelling the guide -1 or 21 down or away during spoolchanging or create enough space of the unhindered, rapid completion ofthis operation. In addition, the arrangement can also be used asa veryeffective switch for switching the individual twisting or winding uniton and off. By locking the yarn guide after it has been tilted or swungdown, it is also possible to prevent the twisting or winding unit frombeing unintentionally switched on'again. In large multispindle twistingmachines with many units placed closely together, the switch-offassembly of the invention has proven to be most effective.

The invention is hereby claimed as-follows:

1. In a textile machine having a plurality of spindles representingindividual operating units arranged on a machine frame, each spindlebeing adapted to carry a feed spool from which a thread is supplied in apredetermined balloon path, the improvement of an automatic electricalswitch-off assembly in combination therewith which comprises:

a thread monitor acting simultaneously as aballoon thread guidepositioned to receive said thread in running contact at the requiredheight of the thread balloon during normal operation;

a holder to which said thread monitor is pivotally connected so as to beurged in tilting relationship against the tension exerted by the runningthread, said holder also including means to rotate said thread monitorabout the holder axis laterally away from the axis of the thread balloonpath; and

electrical switching means arranged in said holder for actuation to itsshut off position in response to movement of said thread monitor to itstilted position free of thread tension and also in response to movementof said thread monitor to its rotated position away from said balloonpath.

2. The combination as claimed in claim 1 wherein said holder isadjustably fastened to said machine frame for movement axially parallelto an adjacent spindle to adjustably arrange said balloon thread guidein its required position.

3. The combination as claimed in claim 1 wherein said thread monitor isurged in said tilting relationship by the effect of gravity.

4. The combination as claimed in claiml wherein said thread monitor isurged in'said tilting relationship by spring means arranged on saidholder.

5. The combination as claimed in claim 1 wherein said thread monitor isurged in said tilting relationship by magnetic means arranged on saidholder.

6. The combination as claimed in claim 1 wherein locking means areincluded on said holder to releasably' said thread monitor is anelongated thread guide having a guide eyelet at the free end thereof anda switch actuating element at the other end thereof pivotally mounted ona pin fixed within a housing forming the outer front portion of saidholder, said switch actuating element bearing a protruding cammember'adapted to cooperatively engage the tongue of a microswitchcontained within said housing.

9. The combination as claimed in' claim 8 wherein said housing togetherwith said thread guide is rotatable about a fixed pin protrudingaxiallyforwardly of the rear portion'of said holder. 1

10. The combination as claimed in claim 9 wherein a spring isarrangedaround said protruding fixed pin for compression between aflanged plate mounted on the front of said fixed pin and 'a reentrantannular portion of said housing at the rear end thereof resting on thefront face of said rear portion of the holder.

11. The combination as claimed in claim 10 wherein said flanged plate ofthe fixed pin supports a forwardly curved cam member engaging a guidepin on said switch actuating element, thereby urging said thread guideinto its tilted position as it is simultaneously rotated with saidhousing about the holder axis.

12. The combination as claimed in claim 9 wherein a cammed locking pinis arranged on the front cover portion of said housing for rotation onan axis parallel to the pivot axis of the thread guide and switchactuating element, said locking pin being rotatable between an openp'dsition and a closed locking position of the cam against said threadguide holding it in its tilted position.

13. The combination as claimed in claim 9 including a slide memberarranged in a slot of said housing adjacent its front cover such that itcan be slidably inserted between said cover and said switch actuatingelement to hold said thread guide in its tilted position.

14. The combination as claimed in claim 9 including a spring loadingsaid switch actuating element against the tension exerted by the runningthread on said thread guide and moving said thread guide to its fullytilted position in the absence of thread tension.

1. In a textile machine having a plurality of spindles representingindividual operating units arranged on a machine frame, each spindlebeing adapted to carry a feed spool from which a thread is supplied in apredetermined balloon path, the improvement of an automatic electricalswitch-off assembly in combination therewith which comprises: a threadmonitor acting simultaneously as a balloon thread guide positioned toreceive said tHread in running contact at the required height of thethread balloon during normal operation; a holder to which said threadmonitor is pivotally connected so as to be urged in tilting relationshipagainst the tension exerted by the running thread, said holder alsoincluding means to rotate said thread monitor about the holder axislaterally away from the axis of the thread balloon path; and electricalswitching means arranged in said holder for actuation to its shut offposition in response to movement of said thread monitor to its tiltedposition free of thread tension and also in response to movement of saidthread monitor to its rotated position away from said balloon path. 2.The combination as claimed in claim 1 wherein said holder is adjustablyfastened to said machine frame for movement axially parallel to anadjacent spindle to adjustably arrange said balloon thread guide in itsrequired position.
 3. The combination as claimed in claim 1 wherein saidthread monitor is urged in said tilting relationship by the effect ofgravity.
 4. The combination as claimed in claim 1 wherein said threadmonitor is urged in said tilting relationship by spring means arrangedon said holder.
 5. The combination as claimed in claim 1 wherein saidthread monitor is urged in said tilting relationship by magnetic meansarranged on said holder.
 6. The combination as claimed in claim 1wherein locking means are included on said holder to releasably maintainsaid electrical switching means in the shut off position.
 7. Thecombination as claimed in claim 6 wherein said locking means holds saidthread monitor in its tilted position corresponding to the shut-offposition of said electrical switching means.
 8. The combination asclaimed in claim 1 wherein said thread monitor is an elongated threadguide having a guide eyelet at the free end thereof and a switchactuating element at the other end thereof pivotally mounted on a pinfixed within a housing forming the outer front portion of said holder,said switch actuating element bearing a protruding cam member adapted tocooperatively engage the tongue of a microswitch contained within saidhousing.
 9. The combination as claimed in claim 8 wherein said housingtogether with said thread guide is rotatable about a fixed pinprotruding axially forwardly of the rear portion of said holder.
 10. Thecombination as claimed in claim 9 wherein a spring is arranged aroundsaid protruding fixed pin for compression between a flanged platemounted on the front of said fixed pin and a reentrant annular portionof said housing at the rear end thereof resting on the front face ofsaid rear portion of the holder.
 11. The combination as claimed in claim10 wherein said flanged plate of the fixed pin supports a forwardlycurved cam member engaging a guide pin on said switch actuating element,thereby urging said thread guide into its tilted position as it issimultaneously rotated with said housing about the holder axis.
 12. Thecombination as claimed in claim 9 wherein a cammed locking pin isarranged on the front cover portion of said housing for rotation on anaxis parallel to the pivot axis of the thread guide and switch actuatingelement, said locking pin being rotatable between an open position and aclosed locking position of the cam against said thread guide holding itin its tilted position.
 13. The combination as claimed in claim 9including a slide member arranged in a slot of said housing adjacent itsfront cover such that it can be slidably inserted between said cover andsaid switch actuating element to hold said thread guide in its tiltedposition.
 14. The combination as claimed in claim 9 including a springloading said switch actuating element against the tension exerted by therunning thread on said thread guide and moving said thread guide to itsfully tilted position in the absence of thread tension.